Inspection Procedure 5: The A/C compressor does not work

COMMENTS ON TROUBLE SYMPTOM

If the A/C compressor does not work, inadequate refrigerant quantity or the A/C compressor circuit is suspected..

POSSIBLE CAUSES

Malfunction of A/C compressor
Malfunction of A/C compressor relay
Damaged harness wires and connectors
Malfunction of engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-33 A/C compressor connector and C-105 engine-ECU

Q. Is the check result normal?

Go to Step 2.

Repair the connector.

STEP 2. Voltage measurement at A-33 A/C compressor connector.

(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the "ON" position.

(3)Disconnect engine-ECU connector C-105 and earth terminal 40.

(4)Voltage between terminal 1 and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 11.

Go to Step 3.

STEP 3. Connector check: A-21X A/C compressor relay connector

Q. Is the check result normal?

Go to Step 4.

Repair the connector.

STEP 4. Check the A/C compressor relay continuity.

Refer to

Q. Is the A/C compressor relay in good condition?

	Go to Step 5.

	Replace the A/C compressor relay.

STEP 5. Voltage measurement at A-21X A/C compressor relay connector.

(1)Remove the relay, and measure at the relay box side.
(2)Turn the ignition switch to the "ON" position.

(3)Voltage between terminal 1 and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 7.

Go to Step 6.

STEP 6. Check the wiring harness between A-21X A/C compressor relay connector terminal No.1 and the ignition switch (IG2).

Check the A/C compressor relay power supply line for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Repair the wiring harness.

STEP 7. Voltage measurement at A-21X A/C compressor relay connector.

(1)Remove the relay, and measure at the relay box side.
(2)Turn the ignition switch to the "ON" position.

(3)Voltage between terminal 4 and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 9.

Go to Step 8.

STEP 8. Check the wiring harness between A-21X A/C compressor relay connector terminal No.4 and the fusible link (20).

Check the A/C compressor relay power supply line for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Repair the wiring harness.

STEP 9. Check the wiring harness between A-21X A/C compressor relay connector terminal No.3 and A-33 A/C compressor connector terminal No.1.

note

Prior to the wiring harness inspection, check intermediate connector A-28 and A-27, and repair if necessary.

Check the A/C compressor relay power supply line for open circuit.

Q. Is the check result normal?

Go to Step 10.

Repair the wiring harness.

STEP 10. Check the wiring harness between A-21X A/C compressor relay connector terminal No.2 and C-105 engine-ECU connector terminal No.40.

Check the A/C compressor power supply line for open circuit.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction

Repair the wiring harness.

STEP 11. Check the magnetic clutch operation.

Refer to

Q. Can the sound of the magnetic clutch (click) be heard?

	Go to Step 12.

	Replace the compressor magnet clutch.

STEP 12. Check the refrigerant level.

Refer to

Q. Is the refrigerant level correct?

	Go to Step 13.

	Correct the refrigerant level (Refer to ).

STEP 13. Replace the A/C-ECU, and then recheck the trouble symptom

Check that the compressor works normally.

Q. Is the check result normal?

	This diagnosis is complete.

	Replace the engine-ECU.